International Prognosis Scoring System Research Articles

Involvement of the JAK-STAT pathway in the molecular landscape of tyrosine kinase fusion-negative hypereosinophilic syndromes: A nationwide CEREO study.

We investigated using a custom NGS panel of 149 genes the mutational landscape of 64 consecutive adult patients with tyrosine kinase fusion-negative hypereosinophilia (HE)/hypereosinophilic syndrome (HES) harboring features suggestive of myeloid neoplasm. At least one mutation was reported in 50/64 (78%) patients (compared to 8/44 (18%) patients with idiopathic HE/HES/HEUS used as controls; p < .001). Thirty-five patients (54%) had at least one mutation involving the JAK-STAT pathway, including STAT5B (n = 18, among which the hotspot N642H, n = 13), JAK1 (indels in exon 13, n = 5; V658F/L, n = 2), and JAK2 (V617F, n = 6; indels in exon 13, n = 2). Other previously undescribed somatic mutations were also found in JAK2, JAK1, STAT5B, and STAT5A, including three patients who shared the same STAT5A V707fs mutation and features consistent with primary polycythemia. Nearly all JAK-STAT mutations were preceded by (or associated with) myelodysplasia-related gene mutations, especially in RNA-splicing genes or chromatin modifiers. In multivariate analysis, neurologic involvement (hazard ratio [HR]4.95 [1.87-13.13]; p = .001), anemia (HR 5.50 [2.24-13.49]; p < .001), and the presence of a high-risk mutation (as per the molecular international prognosis scoring system: HR 6.87 [2.39-19.72]; p < .001) were independently associated with impaired overall survival. While corticosteroids were ineffective in all treated JAK-STAT-mutated patients, ruxolitinib showed positive hematological responses including in STAT5A-mutated patients. These findings emphasize the usefulness of NGS for the workup of tyrosine kinase fusion-negative HE/HES patients and support the use of JAK inhibitors in this setting. Updated classifications could consider patients with JAK-STAT mutations and eosinophilia as a new "gene mutated-entity" that could be differentiated from CEL, NOS, and idiopathic HES.

Reclassification of Ascertain (ASTX727-02) Myelodysplastic Syndrome (MDS) Patients: Outcomes Including Clinical Response, Overall Survival (OS), and Leukemia Free Survival (LFS) Based on IPSS-R and IPSS-M Scoring Systems

Background: Oral decitabine/cedazuridine (ASTX727) is a fixed dose combination of decitabine (35 mg) and the cytidine deaminase inhibitor cedazuridine (100 mg) given once daily X 5 days on a 28-day cycle producing pharmacokinetic (PK) exposure equivalent to the standard intravenous (IV) decitabine regimen of 20 mg/m 2 daily X 5 days on a 28-day cycle. This was demonstrated in the pivotal ASCERTAIN study (Garcia-Manero, et al, ASH 2019) as it provided a PK bridge to existing decitabine data and demonstrated median OS was 31.7 mo. (Savona,et al. Intl. MDSF International Congress on MDS, 2021). Subjects were initially classified by the International Prognosis Scoring System (IPSS) for historical reasons, however IPSS-R and IPSS-M are enhancements to IPSS that provide dynamic risk assessment for predicting clinical outcomes in MDS. Here, the objective was to re-classify the MDS subjects enrolled on the ASCERTAIN study by IPSS-R and IPSS-M and measure the impact of informing patient outcomes based on re-calculated risk assessment. Methods: One hundred thirty-three subjects with MDS/CMML (chronic myelomonocytic leukemia) were enrolled in ASCERTAIN and were randomly assigned either IV decitabine for cycle 1 and oral decitabine/cedazuridine for cycle 2 or the opposite treatment sequence. All subjects continuing beyond cycle 2 received oral decitabine/cedazuridine for all subsequent cycles until treatment discontinuation for disease progression, toxicity, patient's decision, or HSCT. Whole blood collected prior to treatment was used for DNA isolation and molecular abnormalities identified using next-generation sequencing (NGS) hematologic malignancy panel of 179 genes including all genes commonly mutated in MDS. In the initial analysis of clinical outcomes, subjects were classified by IPSS with response assessment by IWG 2006 IPSS low and Int-1 risk levels were categorized as lower-risk MDS (LR-MDS), whereas IPSS Int-2 and high-risk categories were categorized as higher-risk MDS (HR-MDS). Subjects with sufficient data based on (e.g., available heme parameters, cytogenetics, NGS etc.) were reclassified by IPSS-R and IPSS-M. Subjects with IPSS-R score of ≤3.5 or IPSS-M of either very low, low, or moderate low were categorized as LR-MDS. Similarly subjects with IPSS-R score of &amp;gt;3.5 or an IPSS-M categorization of either moderate high, high, or very high were categorized as HR-MDS. Reclassified subjects were reassessed for CR (Complete Response), OS, and LFS and Harrell's concordance index (c-index) was used to describe the level of agreement between each scale and outcomes. Results: Based on the available data, the number of MDS subjects in the different risk classifications were the following: IPSS: 117, IPSS-R: 104, and IPSS-M: 105. Thirteen and 12 subjects on the IPSS could not be reclassified in the IPSS-R and IPSS-M, respectively, including 5 Int-1 and 2 low-risk MDS cases. CMML subjects were excluded from these analyses. Re-classification generally resulted in the upgrade of the subjects from LR-MDS to HR-MDS (Fig. 1). Thirty-one (26.5%) subjects from IPSS were reallocated in the IPSS-R to different risk categories; 3 (9.7%) were downgraded and 28 (90.3%) were upgraded. Similarly on reclassification with IPSS-M 34 (32.4%) of the patients reclassified; 5 (14.8%) were downgraded and 29 (85.3%) were upgraded. For IPSS LR-MDS, 23.2% of patients achieved CR, and 22.9% in the IPSS HR-MDS. Similarly, 21.6% patients achieved CR in the IPSS-R LR-MDS, and 23.9% in the IPSS-R HR-MDS; 26.3% patients achieved CR in the IPSS-M LR-MDS, and 20.9% in the IPSS-M HR-MDS. The c-index for the IPSS was .64 (OS) and .67 (LFS), IPSS-R was .70 (OS) and .71 (LFS), and .75 (OS) and .78 (LFS) for the IPSS-M (Table1). Conclusion: Reclassification from IPSS to IPSS-R or IPSS-M upgraded multiple subjects from a LR to a HR category, describing the ASCERTAIN patient population as a majority higher risk population with worse prognosis than previously assumed based on the IPSS. The efficacy as measured by the CR rates did not change when the LR and HR categories were defined by the different risk stratification systems. In contrast, the c-index improves with migration from IPSS to IPSS-R to IPSS-M, indicating an increased discriminatory ability of IPSS-M score in comparison to IPSS and IPSS-R, to predict patient outcomes.

Five-Year Follow up Results of Phase II Clinical Trial Evaluating Ruxolitinib (RUX) and Azacitidine (AZA) Combination Therapy in Patients (pts) with Myelodysplastic Syndrome/Myeloproliferative Neoplasms (MDS/MPNs)

Introduction: MDS/MPN represent a distinct category of Philadelphia chromosome negative myeloid neoplasms that share pathological and morphological characteristics with both MDS and MPN. Very few prospective studies have been conducted in pts with MDS/MPN, with currently available data showing a median overall survival (OS) of less than two years in this challenging subset. We conducted a phase 2 clinical trial evaluating the combination of JAK-inhibitor RUX with demethylating agent AZA in pts with MDS/MPN. The interim analyses (Assi et al, AJH 2018) showed objective responses in 57% pts and a median duration of response (DOR) of 8 months (mos). Herein we report the long-term follow up of a larger cohort of pts treated on this prospective ongoing clinical trial. Methods: We conducted an open label single-arm phase 2 clinical trial (NCT01787487) at the MD Anderson Cancer Center, Houston, evaluating the use of RUX-AZA in newly diagnosed or previously treated MDS/ MPN. Adults aged ≥ 18 years with MDS/MPN categorized as Intermediate 1-2 or High-risk by Dynamic International Prognosis Scoring System (DIPSS) (Passamonti et al, Blood 2010) were included. Pts previously exposed to RUX and/or AZA were excluded. RUX 5-20mg twice daily (per RUX label depending upon platelet counts at initiation) was given in 28-day cycles, and AZA 25mg/m2 (SQ or IV) Days 1- 5 was added starting cycle 4. Cycles were repeated every 4-6 weeks depending on count recovery. Response assessment was carried out using the 2015 International Consortium Proposal of response MDS/MPN criteria (Savona M et al, Blood 2015) and best objective response was tabulated. Progression free survival (PFS) included treatment change because of disease progression or inadequate response, transformation to acute myeloid leukemia (AML) or death and calculated from the time of therapy initiation. Results: From May 2013 to August 2022, 52 pts with a median age of 68 years (range, 39-82 years) were treated on trial. The data cutoff was July 15, 2023 ( Table 1). 32 pts (61%) were males, and 9 (75%) pts were white. 50 pts (96%) had ECOG PS&amp;lt;2. Baseline median bone marrow (BM) blasts were 4.5% (range 0-19%), with 19 (37%) carrying JAK2 mutations, and 16 (31%) with an abnormal karyotype. Intermideate-2 DIPSS was the most prevalent risk category, seen in 23 (44%) pts. At least one cytopenia was present in 32 (61%) pts, and three (6%) pts had bicytopenia. 24 of 49 (49%) had palpable splenomegaly, and 3 pts had undergone prior splenectomy. After a median follow up of 60 months (mos) (95% CI: 50.0-71.3) from therapy initiation, 18 (35%) pts are alive, and 1 pt is on active trial therapy. Objective responses per the MDS/MPN international consensus response criteria were observed in 28 (54%) pts and included clinical improvement in 14 (50%) pts, partial marrow response in 12 (43%) pts, optimal marrow response and cytogenetic complete remission in 1 (4%) pt each. The DOR in the 28 pts with objective response to therapy (censored for death in pts who died without evidence of progression) was 35 mos (95% CI: NE-73.5). The median OS in this group of responders was 36.4 mos (95% CI: NE-77.2). Five of these pts died without confirmed disease progression at the time of death. For the full cohort the median PFS was 13.4 mos (95% CI: 7.9-18.8) and median OS was 31.8 mos (95% CI: 18.5-44.9 ) (Figure 1). Transformation to AML occurred in 12 (23%) pts, with the median time to transformation being 13.2 mos (range 2.9-71.3) and all of them have died at the time of last follow-up. 8 (15%) pts underwent allogenic stem cell transplant (ASCT) as subsequent therapy following treatment with AZA-RUX amongst whom 6 (75%) had shown objective responses prior to transplant. For the pts who underwent ASCT, median PFS from the initiation of AZA-RUX was 40.8 months and median OS was not reached. Conclusion: Long term follow up from this phase II prospective clinical trial demonstrates durable disease responses with the RUX-AZA combination in MDS/MPN, with the responses translating into improved survival outcomes.

Myelodysplastic Syndrome Associated Hemophagocytic Lymphohistiocytosis: A Retrospective Study of 15 Cases in a Single Center

Introduction: Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disorder characterized by excessive cytokine secretion, resulting in hyperinflammation and multiorgan dysfunction. It is classified into primary HLH, which is mainly caused by genetic defects, and secondary HLH, triggered by various underlying conditions. Malignancy-associated HLH (M-HLH) is a secondary form commonly observed in patients with hematological malignancies, such as lymphomas, T/NK-cell disorders, acute leukemias, lymphoproliferative diseases, and myelodysplastic syndrome (MDS). M-HLH can occur in up to 1% of patients with hematologic malignancies, with lymphoma being the most frequently associated malignancy. HLH initiated by MDS is a rare entity with only a few cases reported, leading to limited knowledge regarding its pathogenesis, diagnosis and optimal treatment strategies. Methods: In this retrospective study, we analyzed a consecutive series of MDS-HLH patients admitted to our center between March 1, 2019, and March 1, 2023. Bio-clinical data related with MDS and HLH were collected at diagnosis of MDS-HLH. Additional observational indicators encompassed the following: basic clinical characteristics of the patients (age at onset, gender, duration of MDS prior to HLH), correlation between the onset of HLH and MDS, treatment and response, and genetic defects associated with HLH and MDS. MDS risk classification was according to the Revised International Prognosis Scoring System (IPSS-R) and the WHO classification-based Prognosis Scoring System, while patients were categorized into two groups as higher-risk and lower-risk MDS-HLH group. The follow-up period started at the time of MDS-HLH diagnosis and ended at the date of death or last examination. Overall survival (OS) was calculated from the time of HLH diagnosis to the date of death from any cause. Results: A total of 15 patients diagnosed with MDS-HLH were included in the study, with a median age of 66 years (range, 33-83 years). The majority of patients (10/15, 67%) were over 60 years old. All patients exhibited typical features of aggressive HLH: fever, cytopenia and elevated serum ferritin in all patients, hepatomegaly/splenomegaly in 87% (13/15), hypofibrinogenemia/hypertriglyceridemia in 73% (11/15), hemophagocytosis in 73% (11/15), low NK-cell activity in 21% (3/14), and elevated levels of sCD25 in 93% of patients (14/15). Additionally, four patients (27%) had concurrent Epstein-Barr virus (EBV) infection. Further analysis comparing the lower-risk and higher-risk MDS-HLH groups revealed interesting findings. In the lower-risk group, all patients developed HLH concurrently with the diagnosis of MDS. However, in the higher-risk group, the majority of patients (6/8, 62.5%) experienced HLH onset during MDS progression or relapse (p=0.014). Among the 15 patients, 8 patients (53.3%) achieved remission of HLH. During the study period, 8 deaths occurred, all directly attributed to HLH or its complications. The majority of deaths (75%, 6/8) occurred within the first two months after HLH diagnosis. The median overall survival was 12.3 weeks (95%CI, 1.1-23.5). Patients who achieved complete or partial response had significantly prolonged overall survival compared to those who did not respond to treatment (p=0.002). In the multivariate analysis of prognosis, the remission status of HLH was the only factor which was significantly associated with survival (p=0.018, Exp(B)=0.003). Conclusion: This is the first comprehensive study focusing specifically on MDS-HLH, providing valuable insights into the clinical characteristics, treatment outcomes, and prognosis of MDS-HLH. The findings emphasize the need of considering revision of diagnostic criteria specially for MDS-HLH. The pathogenesis of HLH in MDS-HLH differs based on the risk classification of MDS, with higher-risk cases driven by malignancy and lower-risk cases associated with immune dysfunction. The prognosis of MDS-HLH is generally poor. Achieving remission of HLH is crucial for improving the prognosis of MDS-HLH patients. Conventional chemotherapy regimens, including etoposide, have shown limited efficacy and safety in this context. Chemotherapy-free regimens should be preferred considering the features of ineffective hematopoiesis in MDS. The role of EBV infection in MDS-HLH development should be recognized.

Prospective Follow-up of Patients with Myelofibrosis (MF) and Treated with Ruxolitinib in France: The Rumycup Study

Introduction MF is a clonal blood disease affecting 1.5 per 100,000 people worldwide. MF is characterized by megakaryocytic proliferation and atypia, usually accompanied by reticulin and/or collagen fibrosis, splenomegaly, anemia, and constitutional symptoms. Current treatments for MF are palliative, aiming to alleviate symptoms and restore quality of life. Ruxolitinib (Jakavi®) is an oral JAK1/JAK2 inhibitor, first in its class, and currently approved in >90 countries for the treatment of splenomegaly or disease-related symptoms in patients with MF. This study aimed to evaluate the use and outcome of ruxolitinib therapy during the first year after initiation in clinical practice. Methods RUMYCUP was a French, multicenter, non-interventional, prospective study. Adult patients with MF primary or secondary to polycythemia vera (PV) or essential thrombocythemia (ET) and for whom a decision was taken to initiate treatment with ruxolitinib, were included in the study. Primary data were collected at inclusion and at 3, 6, 9 and 12 months. The primary objective of this study was to assess ruxolitinib exposure during 11.5 months after treatment initiation. The secondary objectives were to describe patients' characteristics and treatment with ruxolitinib. Results Between Oct-2018 and Sep-2021, 152 patients were enrolled in the study in 49 French centers. Of them, 146 were included in the analysis population and 150 were included in the safety population. Overall, 50.7% of patients (95% CI: 42.3; 59.0) received ruxolitinib for at least 11.5 months, with a higher proportion in patients with splenomegaly at initiation than in those with no or unknown splenomegaly (53.8% vs 37.9%). At inclusion, 58.9% of patients were male, and the mean age was 70.9 years. Half of the patients were diagnosed with primary MF, 33.6% had a post-ET and 15.8% had a post-PV MF. The driver mutations were JAK2V617F in 69.2% of patients, CALR in 11.6%, and MPL in 4.8%. Among patients with available prognostic scores, 30.9% had a high-risk disease, 36.8% and 26.5% had an intermediate 2 or 1 risk disease, respectively, and 5.9% had a low risk disease, based on the International Prognosis Scoring System. At inclusion, 27.4% of patients had hepatomegaly, 32.9% had night sweats, 21.2% had weight loss, and 5.5% had fever. Within the 3 months prior to ruxolitinib initiation, 72.3% of patients did not receive any transfusion of Red Blood Cell (RBC) concentrates, 17.0% had >2 and 10.6% had 1 or 2 RBC transfusions. The median length of the spleen measured by palpation was 8.0 cm below costal margin and the median decrease was of 2.5 cm at Month 12. At inclusion, 58.2% of patients had had at least one previous treatment line and 19.9% two or more lines. As first line, 55.8% of patients received hydroxyurea. During follow-up, <43% of patients received RBC units and <10% of patients received platelet transfusions. Ruxolitinib was initiated at a median dose of 25 mg/day, and the main reasons for starting treatment were splenomegaly (78.1% of patients) and symptoms (58.9%). During follow-up, the dose was increased in 26.7% of patients (mostly for optimization of efficacy), decreased in 14.4% (mostly due to the occurrence of an adverse event [AE], including lack of efficacy) and both increased and decreased in 21.2% of patients. The treatment was temporarily stopped for 20% of patients, for a median 0.5 months. For 27.6% of them, the treatment interruption lasted >21 days. A total of 513 AEs were described in 89.3% of patients. AEs suspected to be related to ruxolitinib were reported in 57.3% of patients, and 58.0% reported 251 serious AEs (SAEs). Overall, 42 SAEs reported in 24 (16.0%) patients led to death. One SAE suspected to be related to ruxolitinib treatment (hemorrhage), led to the death of one patient. The 23 other deaths were not suspected to be related to ruxolitinib treatment and the most frequent SAEs leading to death, were disease progression (5/150 patients) or myelofibrosis and malignant neoplasm progression (3/150), COVID-19 (3/150) and other infections (5/150). Conclusion This 1-year follow-up conducted in France gives a first overview on the exposure to treatment and disease characteristics in patients with MF treated with ruxolitinib in clinical practice. The evaluation in real life conditions showed that half of the patients included in this study maintained ruxolitinib treatment for at least 11.5 months after initiation.

Isocitrate Dehydrogenase 2 Mutation Drives Bone Marrow Macrophage Dysfunction without a Complete Block in Hematopoietic Differentiation

Myelodysplastic syndromes (MDS) represent a broad category of myeloid malignancies characterized by myeloid skewed hematopoiesis, blood cytopenias and increased risk of transformation to leukemia. While not common, isocitrate dehydrogenase 2 (IDH2) mutations are represented in clonal hematopoiesis and in MDS, are found in patients with higher International Prognosis Scoring System (IPSS) disease scores and confer a higher risk of transformation to leukemia. IDH2 mutations lead to metabolic dysfunction and DNA hypermethylation due to the accumulation of D-2-hydroxyglutarate (2HG), an oncometabolite which disrupts hematopoiesis. However, the mechanisms that induces clonal progression and transformation remains incompletely understood. Furthermore, the intrinsic and extrinsic impact of IDH mutation on mature myeloid cell functions and the bone marrow microenvironment (BMME) remains to be elucidated. Using RAW264.7 cells, a monocyte/macrophage-like murine cell line, we retrovirally infected cells with human wt IDH2 or the R172K IDH2 mutant, a common IDH2 mutation. After confirming a 30-fold increase of 2HG (p<.005) and observing evidence of hypermethylation in the IDH2 mutant RAW cells, we tested several key functions of bone marrow macrophages: ability to engulf apoptotic cells (efferocytosis), erythropoietic support, and cytokine production. After labeled apoptotic neutrophils were fed as efferocytic targets to RAW cells at a 10:1 ratio for 6 hours, we observed a 10% decrease of efferocytosis in IDH2 mutants (p < 0.05). Next, we cocultured RAW cells with primary murine late-stage erythroid progenitors and quantified their capacity to form colonies (CFU-E) in the presence of erythropoietin. Compared to wt, IDH2 mutant RAW cells inhibited CFU-E formation by 25% (p < 0.0075). Cytokine array on cell culture supernatant from mutant RAW cells had elevated proinflammatory chemokines/cytokines (CCL5, CXCL10, TNF-a) and decreased cytokines related to inflammation resolution and efferocytosis (GDF-15, Gas6, Endostatin, CCL2). To test these findings further in vivo we generated a murine bone marrow transplant model with retrovirally infected hematopoietic stem cells (HSC: lineage-, c-Kit+, Sca-1+) containing the human wt or R172K IDH2 mutation with an mCherry reporter and transplanted into CD45.1 congenic mice (10 mutant, 10 wt, 1:1 male:female). Mutant IDH2 HSCs demonstrated better engraftment (85-90%) compared to wt (70-80%) and also had higher levels of mCherry positivity within CD45.2+ cells (80-90% mutant vs 40-60% in wt). Longitudinal blood draws showed macrocytic anemia, thrombocytopenia, and elevated reticulocytes in IDH2 mutants by 16 weeks post-transplant. In contrast to current literature, IDH2 mutant cells did not exhibit a complete block in myeloid cell differentiation, as the mutant clone gave rise to mature monocytes, macrophages, and neutrophils. We also harvested bone marrow at 16 weeks post transplantation. Compared to wt IDH2, the mutant IDH2 bone marrow cells exhibited myeloid skewing hematopoiesis and a 3-fold increase in bone marrow monocytes (CD45+, Ly6G-, Ly6C++, F4/80+, p < 0.00001). In the IDH2 mutant bone marrow cells, myeloid progenitors were also expanded: common myeloid progenitors (CMPs: 4-fold increase p < 0.001, CD45+, lineage-, c-Kit+, Sca-1-, CD34+, CD16/32-), and granulocytic monocytic precursors (GMPs: 3-fold increase p < 0.0001, CD45+, c-Kit+, Sca-1-, CD34+, CD16/32+). We also observed a previously unreported loss of long-term hematopoietic stem cells (LT-HSC: 13.5-fold reduction, p < 0.00001, CD45+, lineage-, c-Kit+, Sca-1+, Flt3-, CD48-, CD150+). When cultured ex vivo, there was loss of efferocytic capacity in IDH2 mutant bone marrow derived macrophages fed normal apoptotic neutrophils at a 10:1 ratio for 3 or 24 hours. In summary, we identify defects in efferocytic function and cytokine production in monocytes and macrophages derived from IDH2 mutant hematopoietic stem and progenitor cells. We have previously shown that defects in the efferocytic function of bone marrow macrophages induce increases in inflammatory signals and contribute to skewing of hematopoiesis. Since these macrophage dysfunctions have not previously been attributed to IDH2 single mutation, they represent a potential novel mechanism that could alter the bone marrow microenvironment and impact progression of MDS and transformation to leukemia.

RUNX1 Expression Can be Complementary to RUNX1 Mutation in MDS Prognostication

▪RUNX1 is a member of the core-binding factor family of transcription factors and is imperative for establishing definitive haematopoiesis. Mutated RUNX1 is an adverse risk factor for myelodysplastic syndrome (MDS) and acute myeloid leukaemia (AML). Meanwhile, high expression of RUNX1 is correlated with dismal prognosis in cytogenetically normal AML patients and critical for maintaining leukemic stem cells across AML genetic subgroups. However, the clinical relevancy of RUNX1 expression in MDS patients remains elusive. This study aimed to investigate the prognostic and biologic impacts of RUNX1 expression in MDS patients. We recruited 341 primary MDS patients who had enough bone marrow (BM) samples for RNA and next-generation sequencing. We first examined the difference in RUNX1 expression among patients with wild RUNX1 and N-terminal or C-terminal RUNX1 mutation. Among the 341 patients, 54 (15.8%) harboured RUNX1 mutation, 15 (27.8%) in N-terminal and 39 (72.2%), C-terminal. Patients with C-terminal RUNX1 mutant had higher RUNX1 expression than those with N-terminal RUNX1 mutant or wild RUNX1 (p<0.001 ). Patients were then divided into two groups with higher- and lower-RUNX1 expression (median as cut-off). Higher RUNX1 expression was closely associated with lower platelet counts, higher blast percentages in the BM and peripheral blood and complex karyotypes at diagnosis. Patients with higher-RUNX1 expression were more frequently categorized into higher-risk groups based on the revised international prognosis scoring system (IPSS-R). Higher RUNX1 expression was intimately associated with ASXL1, NPM1, RUNX1, SRSF2, STAG2, TET2, TP53, and ZRSR2 mutations, whereas lower RUNX1 was associated with SF3B1 mutation.Regarding survival, we first examined the impact of RUNX1 mutation on survival in this cohort. As expected, patients with mutated RUNX1 had significantly inferior leukaemia-free survival (LFS) and overall survival (OS) than those with unmutated RUNX1 (p=0.007, and p=0.008, respectively). We then explored the effects of RUNX1 expression on patients' survival. Patients with higher RUNX1 expression had significantly inferior LFS and OS than those with lower expression (both p<0.001, Figure 1a and 1b). We further interrogated RUNX1 expression and mutation statuses for risk stratification. The higher-RUNX1 group consistently had shorter LFS and OS than the lower-RUNX1 group no matter RUNX1 was mutated or not (Figure 1c-1f). Subgroups analysis revealed the same findings in IPSS-R lower-risk (very low, low, and intermediate-risk) and IPSS-R higher-risk (high and very high risk) subgroups (all p<0.05). Moreover, time-dependent ROC curves indicated that RUNX1 expression had better predictive power for LFS and OS than RUNX1 mutation. In multivariate analysis, higher RUNX1 expression appeared as an independent adverse risk factor for LFS and OS irrespective of age, IPSS-R, and mutations in ASXL1, EZH2, RUNX1, SF3B1, SRSF2, STAG2, TET2, and TP53 (Table). The prognostic significance of RUNX1 expression was further validated in two external public cohorts, GSE 114922 and GSE15061. Patients with higher-RUNX1 expression consistently had significantly inferior survival than those with lower-RUNX1 expression (Figure 2). Bioinformatic analysis revealed that higher-RUNX1 patients had more robust IL-17 and MAPK signallings but exhausted antioxidant activities and antimicrobial humoral responses. In summary, we present the characteristics and prognosis of MDS patients with various RUNX1 expressions and propose that RUNX1 expression can complement RUNX1 mutation in MDS prognostication, wherein patients with wild RUNX1 but high expression may need more proactive treatment. [Display omitted] DisclosuresTien: AbbVie: Honoraria; Celgene: Honoraria, Research Funding; Novartis: Honoraria. Chou: Abbvie: Honoraria, Other: Advisory Board, Research Funding; Celgene: Honoraria, Other: Advisory Board, Research Funding; IQVIA: Honoraria, Other: Advisory Board; Pfizer: Honoraria, Other: Advisory Board; Novartis: Honoraria, Other: Advisory Board; Bristol Myers Squibb: Honoraria, Research Funding; Kirin: Honoraria, Research Funding.

The High NRF2 Expression Confers Chemotherapy Resistance through Upregulated DUSP1 in Myelodysplastic Syndromes

Myelodysplastic syndromes (MDS) are a diverse group of clonal marrow stem cell disorders characterized by ineffective hematopoiesis and dysplasia of the cellular elements. Although low-dose cytarabine (Ara-c) has been considered as one of the frontline therapies for high-risk MDS, the overall response rate of single Ara-c treatment was only 30%~40%. Nuclear factor erythroid 2-related factor 2 (NRF2), a basic leucine zipper transcription factor, has been reported to play a pivotal role in chemical detoxification. It is not yet known whether NRF2 has utility as a prognostic biomarker, or whether an elevated NRF2 level is associated with Ara-c resistance in MDS patients.To investigate the expression and effects of NRF2 in MDS patients, gene set enrichment analysis (GSEA) and immunohistochemistry (IHC) were performed. GSEA in a published MDS cohort (n=183) revealed that expressions of NRF2 target genes was significantly enriched in high risk MDS (REAB-1/2) compared to low-risks (RARS and RA). We further detected NRF2 expression levels using IHC staining in the bone marrow (BM) biopsies from a cohort of MDS patients (n=111). Consistent with GSEA results, our IHC data indicated that the NRF2 expression levels of BM from high-risks exceeded low-risk MDS patients by Revised International Prognosis Scoring System (IPSS-R). Importantly, MDS patients with higher NRF2 levels (IHC scores, 4~6) displayed worse overall survival (OS) than patients with lower NRF2 levels (IHC scores, 0~3) (median, 15.7 vs. 22.7 months, P=0.007). Subgroup analysis showed that higher NRF2 levels correlated with poor OS only in chemotherapy group (P=0.04) but not in decitabine (P=0.38) or supportive care group (P=0.19).To recapitulate our findings regarding the function of NRF2 in chemo-resistance, we performed in-vitro and in-vivo experiments. All experiments were performed both in human MDS-derived cell line SKM-1 and MDS mouse model cell line RUNX1 mutant-transduced MllPTD/WT BM cells (MllPTD/WT/RUNX1-S291fs). The cytotoxicity of Ara-c was determined by calculating the half maximal inhibitory concentration (IC50). NRF2 downregulation in MDS cell lines, by inhibitor luteolin, increases IC50 of Ara-c. On the contrary, upregulation of NRF2, mediated by agonist sulforaphane, induces resistance of MDS cells to Ara-C. To better define how suppression of NRF2 sensitized MDS cells to Ara-c, we used lentivirus-mediated shRNA for knockdown of NRF2. Knockdown of NRF2 markedly enhanced early and late apoptosis in MDS cell lines treated with Ara-c. We also established xenograft mouse models through intravenously injecting NRF2 shRNA or scramble shRNA SKM-1 cells into NOD/SCID-IL2Rγnull-SGM3 (NSGS) mice. Knockdown of NRF2 significantly sensitized tumors to Ara-c in our SKM-1 transplanted mouse model. To further investigate the mechanisms involved in NRF2-mediated Ara-c resistance, we analyzed published gene-expression profiles of a large cohort of MDS patients (n=183) and Ara-C sensitive (IC50 <6 μM AraC) and resistant (IC50 >80 μM) AML patient samples (n=10). The data indicated that a group of NRF2 target genes might be responsible for Ara-C resistence. Interestedly, DUSP1 was one of the genes upregulated in both high-risk MDS patients and Ara-c resistant AML patients. Our chromatin immunoprecipitation (ChIP) and qPCR results validated that DUSP1 was a NRF2 direct target gene. Importantly, downregulation of DUSP1 by inhibitor or lentivirus shRNA could abrogate Ara-c resistance in NRF2 elevated MDS cell lines, indicating that NRF2 confers Ara-c resistance partly through its downstream target gene DUSP1 in MDS cells.In conclusion, our clinical and experimental results reveal that 1) NRF2 expression levels are elevated in high-risk MDS patients and serve as a statistically significant prognostic variable for OS in patients with MDS, especially for MDS patients who have received chemotherapy. 2) Pharmacological inhibition of NRF2 re-sensitizes MDS cells to Ara-c treatment while activation of NRF2 by agonist resulted in the reduced sensitivity to Ara-c. 3) NRF2 mediates Ara-c resistance through its direct target gene DUSP1 . Taken together, our findings suggest that silencing NRF2 sensitizes MDS cells to Ara-c treatment; targeting NRF2 in combination with conventional chemotherapy could pave the way for high risk MDS therapy. DisclosuresNo relevant conflicts of interest to declare.

Deregulated Expression of Long Noncoding RNAs H19, LEF1-AS1, TCL6, and WT1-AS1 Predicts Poor Outcome of Patients with Myelodysplastic Syndromes

INTRODUCTIONMyelodysplastic syndromes (MDS) are a heterogeneous group of clonal hematopoietic stem cell (HSC) disorders characterized by dysplastic and ineffective blood cell production and a tendency for transformation to acute myeloid leukemia (AML). Because of the heterogeneity of MDS, the development of additional molecular tools able to refine the Revised International Prognosis Scoring System (IPSS-R), predict outcome and monitor the response to treatment would be highly beneficial.Long noncoding RNAs (lncRNAs) are protein-noncoding RNAs that play multiple roles in hematopoietic differentiation. They contribute to the pathogenesis of hematologic malignancies, representing a new class of potential biomarkers and therapeutic targets. AIMSIn this study, we aimed to identify lncRNAs with deregulated expression in MDS that could serve as novel potential molecular markers of poor outcome. METHODSThe discovery cohort included 54 MDS patients, 14 AML patients with myelodysplasia-related changes (AML-MRC), and 9 controls. Agilent microarrays were used to profile lncRNAs expression in CD34+ bone marrow (BM) cells. Data analyses were focused on the identification of lncRNAs with altered levels between MDS patients (i) with (very) low vs. (very) high risk IPSS-R, and (ii) with progression-free survival (PFS) shorter vs. longer than 2 years. RT-qPCR was applied to validate expression levels of selected deregulated lncRNAs (H19, TCL6, LEF1-AS1, and WT1-AS) and levels of their protein-coding counterparts (LEF1 and WT1) in an independent validation cohort (79 MDS and 14 AML-MRC patients, and 13 controls). Further, we examined whether the expression of H19, TCL6, LEF1, and WT1 changed in patients treated with azacitidine (AZA). For this purpose, we retrieved data from our previous microarray analysis (GEO GSE77750) performed on a cohort of 19 MDS, 3 chronic myelomonocytic leukemia (CMML), 10 AML-MRC patients and 10 controls. RESULTSIn the MDS patients with higher risk IPSS-R, 23 lncRNAs were downregulated (e.g., CXADRP3, LEF1-AS1, PCED1B-AS1, SLC8A-AS1, and TCL6) and 35 lncRNAs were upregulated (e.g., BCAR4, FAM225A, FARP1-AS1, H19, and RBPMS-AS1) vs. lower risk IPSS-R (|logFC| ≥ 1, p ≤ 0.01). Furthermore, we identified significant upregulation of e.g. H19, SATB2-AS1, and WT1-AS in patients with PFS < 2 years vs. those with longer survival.For subsequent study, we selected H19, LEF1-AS1, TCL6, and WT1-AS lncRNAs based on their known association with hematopoiesis. In the validation cohort, we proved that downregulation of LEF1-AS1 and TCL6 and upregulation of H19 and WT1-AS were associated with poor PFS and OS (p < 0.01, Figure 1). Further, we correlated lncRNA expression levels with multiple clinical parameters (sex, age, BM blasts, hemoglobin, neutrophils, platelets, and IPSS-R-based cytogenetics) and found out that only level of H19 was independent from all these variables whereas expression of other lncRNAs was associated with BM blast count. Multivariate analysis confirmed that H19 level, BM blasts, and platelets remained independent factors for OS and PFS in MDS (p < 0.05). Importantly, WT1-AS level, platelets, and hemoglobin were identified as independent variables for survival of MDS patients with BM blast counts < 5 % (p < 0.05). Additionally, we measured levels of appropriate protein-coding counterparts of LEF1-AS1 (i.e. LEF1) and WT1-AS (i.e. WT1) and found strong positive correlation between these pairs (p < 0.001), indicating their co-transcriptional regulation.Because expression of the studied lncRNAs significantly varied between lower and higher risk MDS patients, we further investigated impact of AZA treatment on the expression of H19, TCL6, LEF1, and WT1 in higher risk disease. However, we detected neither any difference in their expression between responders and nonresponders nor any significant return to normal expression levels caused by AZA therapy. CONLUSIONSOur data proved that particular lncRNAs are specifically deregulated in higher risk MDS. Altered transcript levels of these lncRNAs may serve as independent markers of poor survival, even in the patients with low BM blast counts, providing additional information about prognosis of MDS patients beyond the currently used scoring system.The work was supported by grants 17-31398A, 16-33617A, 16-33485A, and 00023736 from the Ministry of Health of the Czech Republic. DisclosuresNo relevant conflicts of interest to declare.

A Leukemic Stem Cell Signature-Based Scoring System for Predicting Prognosis in Myelodysplastic Syndrome Patients

Leukemic stem cells (LSCs) possess biological properties shared with normal hematopoietic stem cells. They are responsible for chemoresistance and relapse in acute myeloid leukemia (AML). Although myelodysplastic syndrome (MDS) has traditionally been regarded as a “hematopoietic stem cell disorder”, the clinical and biological impact of LSCs on MDS patients are not well defined. To address this question, we used the Affymetrix HTA 2.0 microarray platform to profile 16 out of the 17 recently reported stemness genes (one of them, the ARHGAP22 gene was not included in our array) in our 160 adult primary MDS patients. The diagnoses were based on the 2016 World Health Organization (WHO) classification. Patients with antecedent chemotherapy or hematologic malignancies were excluded. Forty-one (25.6%) patients had MDS with single lineage dysplasia (MDS-SLD), 20 (12.5%) had MDS with ring sideroblasts (MDS-RS), 31 (19.4%) had MDS with multilineage dysplasia (MDS-MLD), 32 (20%) had MDS with excess blasts-1 (MDS-EB1) and 36 (22.5%), MDS-EB2. The risk distribution of the cohort was very-high risk, 15.3%; high risk, 21.3%; intermediate risk, 24.7%; low risk 34.7%; and very-low risk 4% according to the revised international prognosis scoring system (IPSS-R). We identified 4 genes (LAPTM4B, NGFRAP1, NYNRIN, and EMP1) whose expression levels were significantly correlated with overall survival (OS). An LSC4 score (0.731 x LAPTM4B - 1.259 x NGFRAP1 + 0.304 x NYNRIN + 0.231 x EMP1) was constructed based on the weighted sums derived from Cox regression analysis. Higher LSC4 scores were associated with higher IPSS-R scores, complex cytogenetics, and higher incidences of mutations of RUNX1, ASXL1, TP53, SRSF2 and ZRSR2. High-score patients had significantly higher 3-year AML transformation rate (36.3% vs 11.3%, P<0.001), shorter leukemia-free survival (LFS, median, 33.6 months vs not reached, P< 0.001, Figure 1A), and shorter OS (median, 15.9 months vs 77.3 months, P<0.001, Figure 1B). In subgroup analysis, LSC4 score could also well stratify MDS patients with normal karyotype into different risk groups (p<0.001). The prognostic significance of LSC4 scores for LFS, AML transformation rate, and OS still remained valid in both IPSS-R lower-risk (very low, low, and intermediate risk) subgroup (Figures 2A and 2B) and higher-risk subgroup (high and very high risk). In multivariate analysis, higher LSC4 score was an independent adverse risk factor for OS, irrespective of age, IPSS-R, and mutation status of ASXL1, TP53, EZH2, SRSF2, and ZRSR2 (Table). We also well validated the prognostic significance of the LSC4 scores in an independent cohort of 30 MDS patients (Figures 3A and 3B). Interestingly, patients with higher LSC4 scores had a better OS if they received allogeneic transplantation than those who did not. It implied that transplantation might ameliorate the poor survival impact of high LSC4 scores. In conclusion, through comprehensive analysis, we have created a simple and powerful LSC4 scoring system, which serves as an independent prognostic factor for OS and LFS in MDS patients. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Is allogeneic stem cell transplantation for myelofibrosis still indicated at the time of molecular markers and JAK inhibitors era?

The role of allogenic stem cell transplantation (ASCT) is still debated in myelofibrosis (MF). A retrospective analyzed was performed to compare the outcome of 71 patients with intermediate-2 or high-risk Dynamic International Prognosis Scoring System+ (DIPSS+) primary (PMF) or secondary (SMF) myelofibrosis with an indication of ASCT as they ultimately underwent the procedure (n=34) or not (n=37). Five-year overall survival (OS) was not statistically different between both groups (allograft: 52% vs no allograft: 34%, P=.12). However, progression to myelodysplastic syndrome or acute myeloid leukemia at 5years was significantly lower in transplanted patients (14% vs 50%, P=.01). In univariate analysis, 5-year OS was significantly higher for transplanted vs non-transplanted patients with unfavorable karyotype (75% vs 0%, P=.001), SMF (71% vs 20%, P=.001) or high DIPSS+ score (46% vs 15%, P=.03). There was also a trend for better 5-year OS in allografted patients with high JAK2V617F burden (>65%) (75% vs 8%, P=.07). Interestingly, the survival of patients who did not proceed to ASCT was dramatically increased by the use of ruxolitinib. Not all intermediate-2/high-risk DIPSS+ MF patients benefit from ASCT, especially since the introduction of JAK2 inhibitors.

Prognosis of Myelodysplastic Syndromes (MDS) in Patients in the Age of 80 Years and Older: Data from the Regular Care MDS Registry in Germany

▪The international prognosis scoring system (IPSS) and the revised-IPSS were generated with data from 816 and 7,019 patients (pts) from academic centers with a median age of 69 and 71 years (y) respectively. As the median age of pts with MDS receiving care in Germany is 74.9 y and around a quarter of pts are older than 80 y, the aim was to evaluate the meaning of the IPSS and additional risk factors in the older population group.Methods: Pts with written informed consent could be included in the online-registry. Pts were eligible if a bone marrow examination had been performed and if basic data and the quarterly course of the disease were documented. Statistical analysis: Depending on the distributions of each variable frequency tables, means (SD), medians were calculated overall and stratified by age classes. Corresponding overall tests were performed (Chi-square, Kruskal-Wallis). Time dependent survival probabilities from MDS diagnosis were estimated by Kaplan Meier curves (compared using log rank test). Multiple Cox regression models were used to investigate associations between mortality risk and baseline risk factors. Variable selection was performed in the subpopulation of elderly pts based on univariate models and models including all prespecified variables (IPSS, sex, transfusion dependent at diagnosis (Tx at d), primary or secondary MDS, comorbidities). Mortality of pts subgroups was compared and age-sex-standardized with the German population 2013 as given in the Human Mortality Database (www.mortality.org, University of California Berkeley, Max Planck Institute for Demographic Research). Standardized mortality rates (SMR) and 95%-confidence intervals were estimated.Results: Between July 2009 and March 2016 (81 months) 2,118 pts from 90 institutions, mainly outpatient practices, were documented. The median age of the 843 (39.8%) female and 1,275 (60.2%) male pts was 74.9y (min-max: 26.5 - 94.2). 631 patients were excluded from analysis due to missing IPSS risk. The duration of observation, frequencies of IPSS, Tx at d, and the Charlson comorbidity index (CCI) are given in the table.Increased age and IPSS risk were significantly associated with the risk of death. An additional interaction between age and IPSS risk was significant (p=0.0198, Cox model, lower IPSS risk in increased age).In the subgroup of elderly patients (n=332, 147 died) after variable selection, IPSS, gender and Tx at d (22 missings) were significantly associated with the risk of death. Furthermore, even in the low risk group an elevated risk was estimated (SMR 1.773) compared to the normal population in the same age class. SMRs increase with higher IPSS risk.Analysis of comorbidities using CCI showed no significant association with mortality in the low risk group of the elderly patients (n=121, 44 died). Because of low sample sizes in the CCI subgroups the power is small, but even the survival curves did not show a clear trend (p= 0.497).Conclusion: IPSS risk and age are significantly associated with the risk of death. In elderly pts associated risk factors were IPSS, male gender and transfusion at diagnosis. Even the diagnosis of low risk MDS has a negative impact on life expectancy.Supported by an unrestricted grant from Celgene and Novartis. [Display omitted] [Display omitted] [Display omitted] DisclosuresSteinmetz:Vifor: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Research Funding, Speakers Bureau. Haastert:X-Med: Honoraria. Tesch:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Schmitz:Celgene: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Amgen: Speakers Bureau.

Phase 1b/2 Study of the Efficacy and Safety of Sonidegib (LDE225) in Combination with Ruxolitinib (INC424) in Patients with Myelofibrosis

Phase 1b/2 Study of the Efficacy and Safety of Sonidegib (LDE225) in Combination with Ruxolitinib (INC424) in Patients with Myelofibrosis

Use of newer prognostic indices for patients with myelodysplastic syndromes in the low and intermediate-1 risk categories: a population-based study

We aimed to compare the ability of recently developed prognostic indices for myelodysplastic syndromes to identify patients with poor prognoses within the lower-risk (low and intermediate-1) categories defined by the International Prognosis Scoring System (IPSS). We included patients with de-novo myelodysplastic syndromes diagnosed between Nov 29, 1972, and Dec 15, 2011, who had low or intermediate-1 IPSS scores and were in the Spanish Registry of Myelodysplastic Syndromes. We reclassified these patients with the new prognostic indices (revised IPSS [IPSS-R], revised WHO-based Prognostic Scoring System [WPSS-R], Lower Risk Scoring System [LRSS], and the Grupo Español de Síndromes Mielodisplásicos [Spanish Group of Myelodysplastic Syndromes; GESMD]) and calculated the overall survival of the different risk groups within each prognostic index to identify the groups of patients with overall poor prognoses (defined as an expected overall survival <30 months). We calculated overall survival with the Kaplan-Meier method. We identified 2373 patients. None of the prognostic indices could be used to identify a population with poor prognoses (median overall survival <30 months) for the patients with low IPSS scores (1290 individuals). In the group with intermediate-1 scores (1083 individuals), between 17% and 47% of patients were identified as having poor prognoses with the new prognostic indices. The LRSS had the best model fit with the lowest value in the Akaike information criteria test, whereas the IPSS-R identified the largest proportion of patients with poor prognoses (47%). Patients with intermediate-1 scores who were classified as having poor prognoses by one or more prognostic index (646 [60%] individuals) had worse median overall survival (33·1 months, 95% CI 28·4-37·9) than did patients who were classified as having low risk by all prognostic indices (63·7 months, 49·5-78·0], HR 1·9, 95% CI 1·6-2·3, p<0·0001) INTERPRETATION: Recently proposed prognostic indices for myelodysplastic syndromes can be used to improve identification of patients with poor prognoses in the group of patients with intermediate-1 IPSS scores, who could potentially benefit from a high-risk treatment approach. None.

Phase 1b Dose-Escalation Study of Sonidegib (LDE225) in Combination with Ruxolitinib (INC424) in Patients with Myelofibrosis

Background: Ruxolitinib, a Janus kinase (JAK) 1/2 inhibitor, has been shown to effectively reduce splenomegaly, manage myelofibrosis (MF)-related symptoms, and improve survival, but has limited anticlonal activity. Inhibition of hedgehog signaling via therapy with sonidegib, a selective inhibitor of smoothened (SMO), in combination with ruxolitinib reduced white blood cell (WBC) and platelet counts, JAK2 mutant allele burden, and bone marrow (BM) fibrosis in preclinical MF models more than ruxolitinib alone (Bhagwat, ASH 2013). The maximum tolerated dose (MTD) and/or recommended phase 2 dose (RP2D) of sonidegib in combination with ruxolitinib for patients (pts) with MF is being assessed in the phase 1b portion of this phase 1b/2 study (NCT01787552). The safety-expansion cohort is currently ongoing; updated data will be presented. Methods: Adults with primary or secondary (post–polycythemia vera or –essential thrombocythemia) intermediate- or high-risk MF with palpable splenomegaly not previously treated with JAK or SMO inhibitors were eligible. Pts received oral doses of sonidegib once daily (QD) and ruxolitinib twice daily (BID). The first dose level enrolled was sonidegib 400 mg QD + ruxolitinib 10 mg BID. Dose escalations were guided by a Bayesian logistic regression model. In addition to safety and pharmacokinetics (PK), spleen length was assessed by palpation at screening, wk 1, every 2 wk until wk 13, monthly after wk 13, and at the end of treatment. BM fibrosis was assessed in biopsies collected every 24 wk. Results: As of March 26, 2014, 23 pts (16 male) with a median age of 67 y (range, 42-77 y) were treated at 3 dose levels (1: sonidegib 400 mg QD + ruxolitinib 10 mg BID [n = 8]; 2: sonidegib 400 mg QD + ruxolitinib 15 mg BID [n = 10]; 3: sonidegib 400 mg QD + ruxolitinib 20 mg BID [n = 5]). Median (range) levels for hemoglobin, platelet count, and WBC count at baseline (BL) were 102 g/L (64-142 g/L), 232 × 109/L (81-900 × 109/L) and 21 x 109/L (2-59 x 109/L), respectively. Median (range) palpable spleen size at BL was 13 cm (5-38 cm) below costal margin. According to the International Prognosis Scoring System, 5, 7, and 11 pts were intermediate-1, intermediate-2, and high-risk, respectively. At data cutoff, 4 pts had discontinued treatment due to an adverse event (AE), physician decision, progressive disease, or patient decision (n = 1 each). PK parameters and trough levels for both agents generally aligned with single-agent data. Fatigue was the most commonly reported AE regardless of causality (Table). Six serious AEs were reported, 4 at dose level 1 (face edema, hyponatremia, pyrexia, right ventricular failure; n = 1 each) and 2 at dose level 2 (blood creatine kinase [CK] increased; n = 2). Dose-limiting toxicities of grade 3 and 4 CK elevations were reported in 2 pts at dose level 2. At data cutoff, 65% of pts achieved a ≥ 50% reduction in palpable spleen length from BL and 9 pts had resolution of splenomegaly. Conclusions: The evaluated combination doses of sonidegib and ruxolitinib were generally well tolerated in pts with MF, and preliminary efficacy data appear promising. Sonidegib and ruxolitinib in combination did not appear to affect the PK of either agent. Once the MTD and/or RP2D are determined, the safety and efficacy of this combination will be further evaluated in the phase 2 study. Disclosures Gupta:Incyte Corporation: Consultancy, Research Funding; Novartis: Consultancy, Honoraria, Research Funding. Koschmieder:Novartis: Consultancy, Honoraria, Membership on an entity9s Board of Directors or advisory committees, Research Funding, Travel, Accomodation, Expenses Other; Novartis Foundation: Research Funding. Harrison:SBio: Consultancy; Gilead: Honoraria; CTI: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau; Shire: Speakers Bureau. Cervantes:Novartis: Membership on an entity9s Board of Directors or advisory committees, Speakers Bureau; Sanofi-Aventis: Membership on an entity9s Board of Directors or advisory committees; Gilead: Membership on an entity9s Board of Directors or advisory committees. Heidel:Novartis: Honoraria, Membership on an entity9s Board of Directors or advisory committees. Drummond:Novartis: Consultancy, Honoraria, Speakers Bureau. Rey:Novartis: Consultancy. Hurh:Novartis NIBR: Employment. Bao:Novartis Pharmaceuticals Corporation: Employment. Rampersad:Novartis Pharmaceuticals Corporation: Employment, Equity Ownership. Kalambakas:Novartis Pharmaceuticals Corporation: Employment, Equity Ownership. Vannucchi:Novartis: Membership on an entity9s Board of Directors or advisory committees, Research Funding, Speakers Bureau.

IDH mutations are closely associated with mutations of DNMT3A, ASXL1 and SRSF2 in patients with myelodysplastic syndromes and are stable during disease evolution

Current information about clinical significance of IDH mutations in myelodysplastic syndromes (MDS), their association with other genetic alterations and the stability during disease progression is limited. In this study, IDH mutations were identified in 4.6% of 477 patients with MDS based on the FAB classification and in 2.2 % of 368 patients based on the 2008 WHO classification. IDH mutations were closely associated with older age, higher platelet counts, and mutations of DNMT3A (36.4% vs. 8.7%, P < 0.001), ASXL1 (47.6% vs. 22.0%, P = 0.007), and SRSF2 (45.5% vs. 11.8%, P < 0.001). IDH2 mutation was a poor prognostic factor for overall survival in patients with lower-risk MDS, based on international prognosis scoring system (IPSS), FAB classification, WHO classification, or revised IPSS (all P ≦ 0.001), but not in higher-risk groups. Sequential studies in 151 patients demonstrated that all IDH-mutated patients retained the same mutation during disease evolution while none of the IDH-wild patients acquired a novel mutation during follow-ups. In conclusion, IDH mutation is a useful biomarker for risk stratification of patients with lower-risk MDS. IDH mutations are stable during the clinical course. The mutation, in association with other genetic alterations, may play a role in the development, but not progression of MDS.

Myelodysplastic Syndromes

Myelodysplastic syndromes (MDS) are malignant stem-cell diseases that are usually diagnosed in elderly patients who present with anemia or, less commonly, bi- or pancytopenia. Their incidence in persons over age 80 is above 50 new cases per 100,000 persons per year. Their clinical course is highly variable. About one-quarter of all patients with MDS develop acute leukemia. The median survival time from the moment of diagnosis is about 30 months. We selectively searched the PubMed database for pertinent articles and guidelines from the years 2000-2013. We used the search term "myelodysplastic syndromes." MDS are diagnosed by cytology, with consideration of the degree of dysplasia and the percentage of blast cells in the blood and bone marrow, and on a cytogenetic basis, as recommended in the WHO classification. In particular, chromosomal analysis is necessary for prognostication. The Revised International Prognosis Scoring System (IPSS-R) enables more accurate prediction of the course of disease by dividing patients into a number of low- and high-risk groups. The median survival time ranges from a few months to many years. The approved treatments, aside from transfusion therapy, include iron depletion therapy for low-risk patients, lenalidomide for low-risk patients with a deletion on the long arm of chromosome 5, and 5-azacytidine for high-risk patients. High-risk patients up to age 70 who have no major accompanying illnesses should be offered allogenic stem-cell transplantation with curative intent. The cure rates range from 30% to 50%. Mucositis, hemorrhages, infections, and graft-versus-host diseases are the most common complications of this form of treatment. Myelodysplastic syndromes are treated on an individualized, risk-adapted basis after precise diagnostic evaluation and after assessment of the prognosis. More studies are needed so that stage-adapted treatment can be improved still further.

Low RPS14 expression in MDS without 5q ‐ aberration confers higher apoptosis rate of nucleated erythrocytes and predicts prolonged survival and possible response to lenalidomide in lower risk non‐5q‐ patients

Haploinsufficiency of the ribosomal protein S14 (RPS14) has been identified as a causal factor in myelodysplastic syndrome (MDS) with isolated del (5q). This study was carried out to investigate RPS14 expression in MDS without 5q deletion and the role of lower expressed RPS14 plays in pathogenesis and the prognosis and lenalidomide-response predicting of non-5q-MDS. The expression level of RPS14 transcription was detected in 156 MDS patients without 5q-. The apoptosis of bone marrow (BM) nucleated erythrocytes was also analyzed. Furthermore, patient prognosis with lower or normal RPS14 expression was analyzed, and the role of RPS14 expression in lenalidomide-response prediction was evaluated. The reduced RPS14 expression occurred in 83 of 156 (53.2%) non-5q-patients. Patients with RPS14 lower expression presented higher platelet counts in the peripheral blood compared with RPS14 normal patients (P = 0.012). The lower RPS14 expression status was inversely correlated with increased apoptosis ratio in nucleated erythrocytes from BM (r = -0.54, P = 0.013). Patients with lower RPS14 expression have a higher 2-yr survival probability than normal RPS14 cases in the international prognosis scoring system (IPSS) lower risk group (90.8% vs. 71.7%; P = 0.018). A multivariate analysis showed RPS14 expression status was an independent predictor for survival in lower risk MDS patients without 5q deletion. Twelve patients were treated with lenalidomide. Five of seven patients achieved an erythroid response in the lower RPS14 expression group (5/7, 71.4%), compared with zero responses in the five normal RPS14 patients (P = 0.018). Lower RPS14 expression in MDS patients without 5q deletion is associated with increased apoptosis of nucleated erythrocytes in lower risk MDS. Additionally, lower RPS14 predicts prolonged survival and possible response to lenalidomide in lower risk MDS patients.

Low RPS14 Expression in MDS without 5q- Aberration Is Associated with Increased Apoptosis of Erythrocytes and Predicts Prolonged Survival and Possible Response to Lenalidomide in Lower-Risk Patients

Abstract 698 Purpose:Haploinsufficiency of the ribosomal protein S14 (RPS14) has been identified as a causal factor in 5q- syndrome. This study was carried out to investigate RPS14 expression in myelodysplastic syndrome (MDS) without 5q deletion and the role under-expressed RPS14 plays in pathogenesis and the prognosis and lenalidomide-response predicting of non-5q-MDS. Patients and Methods:The expression level of RPS14 transcription was detected in 156 MDS patients without 5q-. The apoptosis index of bone marrow (BM) erythrocytes was also analyzed. Furthermore, patient prognosis with low or normal RPS14 expression was analyzed and the role of RPS14 expression in lenalidomide-response prediction was elevated. Results:The reduced expression of RPS14 occurred in 83 of 156 (53.2%) patients. Patients with RPS14 under-expression presented higher platelet counts in the peripheral blood compared to RPS14 normal patients (p=0.012). RPS14 expression status was inversely corrected with the apoptosis index of erythrocytes from BM (r=-0.54, p=0.013). Patients with low RPS14 expression have a higher two-year survival probability than normal RPS14 cases in the international prognosis scoring system (IPSS) lower-risk group (90.8% vs. 71.7%; p = 0.018). A multivariate analysis showed RPS14 expression status was an independent predictor for survival in lower-risk MDS patients without 5q deletion. Twelve patients were treated with lenalidomide. Five of seven patients achieved an erythroid response in the low RPS14 expression group (5/7, 71.4%), compared to zero responses in the five normal RPS14 patients (p=0.018). Conclusion:Low RPS14 expression is common in MDS patients without 5q deletion and is associated with increased apoptosis of erythrocytes in lower-risk MDS. Additionally, low RPS14 predicts prolonged survival and possible response to lenalidomide in lower-risk MDS patients. Disclosures:No relevant conflicts of interest to declare.

Comparison of Outcomes of Advanced Myelofibrosis Patients Treated with Ruxolitinib (INCB018424) to Those of a Historical Control Group: Survival Advantage of Ruxolitinib Therapy

Abstract 793▪FN2▪This icon denotes a clinically relevant abstract Background:Myelofibrosis (MF) is a myeloproliferative neoplasm associated with splenomegaly, debilitating symptoms, cytopenias and progressive bone marrow fibrosis that leads to early death. Patients (pts) with high-risk MF according to International Prognosis Scoring System (IPSS) have particularly poor outcome with a median survival of 2 years (yrs). No approved or effective therapy exists. Ruxolitinib is a JAK1 and JAK2 inhibitor with established clinical benefit in the treatment of pts with MF by reducing spleen size and improving quality of life. Objective:The objective of this analysis was to compare assorted outcomes of MF pts receiving ruxolitinib to those of a matched historical control group. Methods:Overall survival (OS) of 107 pts enrolled in a Phase I/II trial (INCB18424-251; NCT00509899) and followed at the MD Anderson Cancer Center (MDACC) was compared to that of 310 pts with MF identified in 3 large databases (MDACC, U. of Pavia and Hospital Niguarda cà Granda, Milano) with characteristics that would have allowed them to enroll in INCB18424-251. Thus, the pt features between the 2 groups were matched based on enrollment criteria. Among 107 ruxolitinib treated pts, 63 had high risk, 34 intermediate (int)-2 and 10 int-1 risk according to IPSS. In the control group (n=310), 165 pts had high and 145 pts int-2 risk; most pts were treated with conventional or investigational therapies during follow-up. Results:Ruxolitinib-treated pts had a median age of 66 yrs, hemoglobin (Hb) of 10.2 g/dL, WBC of 19×10^9/L, platelets of 277×10^9/L, and palpable spleen of 19 cm. Control pts had a median age of 70 yrs, Hb of 9.7 g/dL, WBC of 12×10^9/L, platelets of 265×10^9/L, and palpable spleen of 6 cm. Baseline characteristics that differed between 2 groups included: significantly more int-2 vs high-risk pts (according to both IPSS and dynamic IPSS [DIPSS]), older age and lower Hb in the controls, as contrasted to higher WBC and larger spleen in those on ruxolitinib. There were no differences between the groups with regard to male:female ratio, platelet count, and cytogenetic characteristics. With regard to OS comparison between the 2 groups, a significant difference was seen in favor of ruxolitinib (p=0.022). Indeed, 33 of 107 pts (30.8%) in the ruxolitinib group vs. 189 of 310 (60.9%) in the control group died, after a median follow-up of 32 and 22 months, respectively. The difference in OS was highly significant in the high-risk pt subgroup (p=0.006), in that 21/63 (33.3%) vs. 112/165 (67.9%) died in the ruxolitinib and control groups, respectively. In the univariate analysis, significant factors associated with longer OS were int-2 (vs. high) risk (per IPSS/ DIPSS), platelets >400×10^9/L, and age <65 years, but not gender, abnormal cytogenetics, high WBC (>25×10^9/L), anemia (Hb <10g/dL), or spleen size. In the multivariate analysis, using age and blood cell counts as continuous variables, independent significant factors for better survival were IPSS int-2 risk, younger age, higher platelets, and treatment with ruxolitinib (p=0.02; HR=0.63). Conclusions:We have identified a historical control group of pts with clinical characteristics that would have allowed them to participate in the Phase I/II study of ruxolitinib in MF. We compared their survival to 107 pts who participated in that trial, and were followed at the MDACC. The survival of pts with high-risk MF that were treated with ruxolitinib was found to be significantly longer than that of the matched control group. Further, ruxolitinib therapy was identified as an independent factor influencing better survival in the multivariate analysis. Our data suggest the potential of ruxolitinib to change the natural progression of MF pts with advanced disease. [Display omitted] Disclosures:Verstovsek:Incyte Corporation: Research Funding.